Linux – How do I find out how many bytes have been written during a file copy?

Issue

This Content is from SuperUser. Question asked by Humpity

In linux (Ubuntu), I use a file manager to copy a large file e.g (500mb) to a USB sd card.

According to the gui, it shows completion in about 5 or 6 seconds (the destination file size is the same as the source).
But I know it’s not done because the card reader is still blinking and the file manager dialog won’t close.
It’s obvious the copy is being buffered.
Even the terminal command stat -c%s filename shows the full filesize (it’s lying).
After 50 secs, the dialog closes and I know that it’s done.

My question is how do I find out how many ‘actual’ bytes have been written to the sd card at any moment ?
Is there a command that can do this ?



Solution

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